Huang Limei, Li Hao, Wen Shunxi, Xia Penghui, Zeng Fanzhan, Peng Chaoyi, Yang Jun, Tan Yun, Liu Ji, Jiang Lei, Wang Jianfeng
College of Materials Science and Engineering, Hunan University, Changsha, China.
Institute of Laser Manufacturing, Henan Academy of Sciences, Zhengzhou, China.
Nat Commun. 2024 Sep 5;15(1):7777. doi: 10.1038/s41467-024-52264-y.
Hydrogels, provided that they integrate strength and toughness at desired high content of water, promise in load-bearing tissues such as articular cartilage, ligaments, tendons. Many developed strategies impart hydrogels with some mechanical properties akin to natural tissues, but compromise water content. Herein, a strategy deprotonation-complexation-reprotonation is proposed to prepare polyvinyl alcohol hydrogels with water content as high as ~80% and favorable mechanical properties, including tensile strength of 7.4 MPa, elongation of around 1350%, and fracture toughness of 12.4 kJ m. The key to water holding yet improved mechanical properties lies in controllable nucleation for refinement of crystalline morphology. With nearly constant water content, mechanical properties of as-prepared hydrogels are successfully tailored by tuning crystal nuclei density via deprotonation degree and their distribution uniformity via complexation temperature. This work provides a nucleation concept to design robust hydrogels with desired water content, holding implications for practical application in tissue engineering.
水凝胶如果能在所需的高含水量下兼具强度和韧性，在诸如关节软骨、韧带、肌腱等承重组织中具有应用前景。许多已开发的策略赋予水凝胶一些类似于天然组织的机械性能，但会降低含水量。在此，提出了一种去质子化 - 络合 - 再质子化策略来制备含水量高达约80%且具有良好机械性能的聚乙烯醇水凝胶，其拉伸强度为7.4兆帕，伸长率约为1350%，断裂韧性为12.4千焦/平方米。保持水分同时改善机械性能的关键在于可控成核以细化晶体形态。在含水量几乎恒定的情况下，通过去质子化程度调节晶核密度以及通过络合温度调节其分布均匀性，成功地调整了所制备水凝胶的机械性能。这项工作提供了一种成核概念，以设计具有所需含水量的坚固水凝胶，对组织工程的实际应用具有重要意义。
